روى ابن ماجه (738) عَنْ جَابِرِ بْنِ عَبْدِ اللَّه رَضِيَ اللَّهُ عَنْهُما أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ : ( مَنْ بَنَى مَسْجِدًا لِلَّهِ كَمَفْحَصِ قَطَاةٍ ، أوْ أَصْغَرَ ، بَنَى اللَّهُ لَهُ بَيْتًا فِي الْجَنَّةِ ) . صححه الألباني .
Ibn Maajah (738) narrated from Jaabir ibn ‘Abdullah (may Allah be pleased with him) that the Messenger of Allah (blessings and peace of Allah be upon him) said:
“Whoever builds a mosque for the sake of Allah, like a sparrow’s nest or even smaller, Allaah will build for him a house in Paradise.”
Classed as saheeh by al-Albaani.